Corrugated cardboard or paperboard boxes are universally used for the packaging and delivery most commercial products sold in retail and discount stores and supermarkets. These boxes are most commonly constructed of one or more layers of brown kraft paper, a strong and lightweight material that resists tearing, splitting, and bursting. This paper is made from pulped wood chips subjected to a sulfate process to form a fibrous pulp which is then processed on a conventional paper making machine. Once formed, the kraft paper may be cut and folded into paperboard boxes or may be transferred for the construction of corrugated boxes.
In the corrugating process, rolls of kraft paper are fed into a corrugator where it is crimped into a corrugating medium. Layers of uncrimped kraft paper are heated, glued, and pressed on each side of the corrugating medium most typically in an in-line process to form corrugated cardboard. A continuous sheet of corrugated cardboard is cut into wide blanks which are then cut and folded into corrugated boxes.
Due to the fact that corrugated cardboard is an inexpensive and stiff packaging material known to have a high burst strength, millions of tons are produced each year. It is estimated that more than 30 million tons of corrugated and uncorrugated cardboard are produced each year in the United States. The production of this great amount necessarily generates almost an equal amount of cardboard waste resulting from the scraps generated in manufacturing coupled with the waste generated after the useful life of the box has been exceeded. In addition, fast growing pine trees provide the primary source of the wood chips from which the wood pulp is derived. Thousands of acres of land are required to grow these pine trees. After the trees are harvested, the trunks are stripped of their limbs and shipped to the pulp mill.
The volume of natural resources necessary for cardboard and paperboard production, coupled with the waste produced as a result of that production have led to an enormous amount of cardboard and paperboard waste being sent to dumps and landfills. This enormous amount of waste has led to recycling efforts. In fact, many landfills no longer accept corrugated cardboard waste for disposal, or charge a premium (or penalty) to the waste hauler for waste which includes a high content of corrugated cardboard, due to its bulk and its ability to be recycled. Corrugated cardboard is thought to be the largest single source of recovered paper material.
Paperboard and corrugated cardboard waste is collected from recycling stations and shipped to plants where it is pulped and made into new paperboard, cardboard and other paper products. However, it has been found that paperboard, cardboard, and particularly corrugated cardboard can be recycled only a maximum number of times, approximately eight, before the pulp fibers shorten and lose strength and are no longer capable of producing a usable paper. In addition, lower quality paper is commonly used for the corrugating medium thereby limiting the ability to recycle these materials.
Even when paperboard and corrugated cardboard are recycled, however, due to the loss in fiber length and fiber strength, a problem exists in that these fibers cannot alone be recycled into new boxes. Instead the recycled pulp must be added to fresh pulp. In fact, it is known that most recycled paperboard and corrugated cardboard boxes include a maximum of only twenty percent (20%) recycled fibers. As a result, due to the demand for and continued production of paperboard and corrugated cardboard, a greater amount of such materials are produced than are capable of being recycled. A need therefore exists for a product and method of employing a greater percentage of recycled paperboard and corrugated cardboard while still maintaining the required burst strength in the regenerated product.
Historically, cotton fibers were a preferred binder in the manufacture of paper. Cotton fibers produce high quality paper; however, there is a high demand for cotton in textile manufacturing which makes it expensive for paper manufacture. As a result, refined wood pulp replaced cotton in the manufacture of paper due to its relatively inexpensive cost and abundant supply. In the advent of the manufacture of board material such as cardboard and paperboard, cotton was not considered due to its high cost. As a result, such board materials have historically been manufactured using traditional wood pulp as described above. A need, therefore, exists for a process for making a board material which utilizes the abundant supply of post-industrial and post consumer cotton scrap in a nonwoven process utilizing conventional paper making equipment.
As a result of the industrial manufacture of textile products from cotton such as apparel, carpet, furniture, and household goods, an enormous amount of scrap, clippings, imperfect (rejected) waste or scrap material is produced. It is estimated that only about half of this post-industrial (pre-consumer) scrap produced annually is recycled into usable by-products mainly for padding, stuffing, and insulating applications for the automotive, furniture, mattress, coarse yarn, home furnishings, paper, and other industries. In addition, particularly with regard to cotton apparel, and particularly denim fabrics, an enormous amount of post consumer cotton is produced annually. Such post consumer goods have historically had very little commercial value. Due to the limited demand for this material for these uses, an enormous volume of post-industrial and post consumer scrap is either burned or deposited in landfills annually. A need, therefore, exists for a board product and process of manufacture which employs fiber reclaimed from such post industrial and/or post consumer cotton scrap materials.
As a result of the industrial manufacture of other textile products such as apparel, carpet, furniture, and household goods, an enormous amount of cloth scrap, clippings, imperfect (rejected) waste or scrap material is produced. It is estimated that only about half of this post-industrial (preconsumer) scrap produced annually is recycled into usable by-products mainly for padding, stuffing, and insulating applications for the automotive, furniture, mattress, coarse yarn, home furnishings, paper, and other industries. Due to the limited demand for this material for these uses, it is estimated that in excess of 50,000 tons of post-industrial scrap is either burned or deposited in landfills annually. In light of the volume of waste produced and its heavy burden on landfills and waste streams, legislation has been enacted to require the producers of such post-industrial scrap to maintain responsibility over it, even after disposal, and be responsible for the effects caused by the disposal of such scrap. A need, therefore, exists for the development of consumer and/or industrial products which employ fibers reclaimed from such post-industrial scrap materials. In addition, a need exists for the ability to produce board products from reclaimed post-industrial fibers which can be traced back to their source of manufacture.
As a result, the bulk of reclaimed post-industrial fibers have historically been used for padding, stuffing, and insulating applications (downcycle products). A need exists for a board product which benefits from the properties provided by the presence blends of synthetic and natural fibers that can be controlled in the manufacturing process. A need also exists for a product and process which is capable of employing fibers which are nonuniform in their composition.